Disclosed herein are compensating resistance “probing tip” (electrical test probe tip) optimized adapters, and more particularly to compensating resistance electrical test probe tip optimized adapters having compensating resistance (or capacitance) in series or parallel with the transmission path, the compensating resistance probing tip adapters being optimized for use with specific electrical test probes.
A probing system generally includes an electrical test probe for providing an electrical connection between signal testing points of electrical components (e.g. integrated circuits) and testing instruments (e.g. oscilloscopes and other measuring, monitoring, diagnostic, and signal processing instruments). An electrical test probe generally includes a cable (or other transmission path) having a probing head at one end and a testing instrument connector at the other end. The probing head (via at least one probing tip) is for interacting with electrical components. The testing instrument connector is for attaching the cable to testing instruments.
The probing head generally is interconnectable with at least one “probing tip” (electrical test probe tip), which may be an integral probing tip, a removable probing tip, and/or a replaceable probing tip. A socket, spring contact, or other connection means may be used for connecting a removable and/or replaceable probing tip to the probing head. Many probing heads have mechanisms for connecting two probing tips (one of which may be for probing ground). Probing heads may have mechanisms for connecting to more than two probing tips.
Users purchase the electrical test probes based on the performance of the electrical test probes. Accordingly, electrical test probes are carefully designed and tested. Representations and warranties as to the performance of the electrical test probes are made by manufactures and vendors. These representations and warranties are based on how the electrical test probe performs up to a particular mechanical point of contact (a minimal configuration). No representations or warranties are made to the performance of the electrical test probes beyond that particular mechanical point of contact.
Probing tips may be used, for example, for making electrical contact with signal testing points (e.g. components through which an electrical signal is flowing, such as legs of an IC (integrated circuit), pins, leads, paths, or other electrical components) such as those found on a circuit board or other device under test (DUT). Signals may flow from the testing points through a transmission or input path (that extends substantially the length of the probing tip), through the probing head, through the cable, and to the testing instrument.
Probing tips may connect the probing head to signal testing points (also called probing points). Probing tips may also be used to connect the probing head to ground (a special type of probing point). Ground provides the electrical reference point for other signal measurements. In other words, the ground connection typically remains unchanged while the probing head is positioned at (or otherwise interacts with) other signal testing points, so that the electrical signal thereon may be measured, monitored, or otherwise processed. A user may use multiple probing tips for connecting to multiple signal testing points. For example, a user might want to connect to multiple signal testing points to compare signals thereon or to perform operations on signals thereon (e.g. summing operations, differential operations, or quantifying operations). Alternatively, a user may use one probing tip to connect to ground and another probing tip to connect to a signal testing point having an electrical signal thereon.
It is difficult to form a contact with modern miniaturized testing points. For example, both the pins and the spacing between the pins on a modern integrated circuit chip (“IC”) have been miniaturized. When probing for electrical signals in tight spaces, engineers may need to connect two signal testing points simultaneously. This need may arise, for example, as a need to simultaneously connect to a signal testing point and a ground testing point. This need may also arise as a need to connect two signal lines (testing points) in a differential probing setting in an integrated circuit. Tight spaces other than those associated with an integrated circuit might also need to be probed. If two adjacent pins are contacted simultaneously by the probing tip, a short circuit may result between the two adjacent pins. A short circuit may prevent measurement of the desired signal and/or may result in damage to the internal circuitry of the integrated circuit.
In the integrated circuit context, both the signal probing tip and the ground probing tip need to be connected through the legs of the integrated circuit. The distances between the ground testing point and leg testing point to be probed, however, may be variable distances apart, and indeed may change as the desired leg to be probed changes. Thus, a user probing such an integrated circuit needs a flexible multi-spacing method that isolates one leg of such an integrated circuit. This one leg may be a ground or a signal leg. Importantly, when making contact with the legs of the integrated circuit, the probing tips must be electrically isolated from any other integrated circuit legs. If inadvertent electrical contact is made with another leg, a short circuit may result, or an improper reading is possible.
Many solutions to the variable distance problem require a plurality of adapters, each adapter designed for a different distance between integrated circuit legs being probed. This multiple adapter type of solution requires the user to carry extra adapters that can be easily lost. This type of solution also requires the user to remove and replace the adapters which is time consuming and troublesome. This multiple adapter type of solution can also mean that the user does not have the proper adapter. In short, this multiple adapter type of solution is fraught with problems.